| VOACAP Online 11M Coverage Maps |
http://www.voacap.com/11coverage.html |
| NOAA / Space Weather Prediction Center |
http://www.swpc.noaa.gov/radio/ |
| HF Propagation and Solar-Terrestrial Data Website |
http://www.hamqsl.com/solar.html |
| IPS- Global HF - Global Propagation |
http://www.ips.gov.au/HF_Systems/6/1/1 |
